What is the Kuiper Belt
The Kuiper Belt is similar to the asteroid belt found between the orbits of Mars and Jupiter, but it is 20 times as wide and somewhere between 20-200 times more massive. The ices are frozen volatiles that are made up of methane, nitrogen, ammonia and water.
At least three dwarf planets are located in the Kuiper belt: Pluto, Haumea and Makemake. Also, some of the solar system’s moons are thought to have originated there, such as Neptune’s Triton and Saturn’s Phoebe.
The belt is thick in most places and is described as being more torus-shaped than a belt would be. The Kuiper belt shouldn’t be confused with the hypothesized Oort cloud, which is a thousand times more distant.
The objects within the belt, along with the members of the scattered disc and any potential Hill cloud or Oort cloud objects are known collectively as trans-Neptunian Objects (TNO).
Kuiper belt facts
- The Kuiper belt contains millions of icy objects ranging in size from small lumps of ice to large objects of 100 km in diameter or more.
- It is estimated that there are around 35,000 Kuiper belt objects that are larger than 100 km in diameter. This is several hundred times the number and mass of objects found in the asteroid belt.
- There may be as many as 100 million small and faint objects in the belt, with a diameter of 20 km or less. These findings by Anita Cochran and a team of astronomers could not be confirmed by a follow-up Hubble Space Telescope observation though.
- The largest object in the Kuiper belt is the dwarf planet Pluto. Its status as part of the belt is what caused the planet to be reclassified as a “dwarf planet” in 2006.
- Eris is larger than Pluto, however, is is located in the scattered disc – although it is believed that it was originally found in the Kuiper belt.
- Neptune’s moon Triton is also larger than Pluto and is believed to have been captured from the Kuiper belt due to gravitational encounters.
- The first mission to the Kuiper belt and beyond is NASA’s New Horizons which will fly past Pluto in July 2015. It will survey Pluto, Charon, and the other moons before continuing its course to the other objects in the belt and beyond.
- There are structures similar the Kuiper belt around at least nine other stars according to astronomers. The Hubble Space Telescope observed discs around the stars HD 138664 in the Lupus constellation, and from the Carina constellation, HD 53143.